Nottingham X-ray machine enables study of liquid surfaces

Nottingham University will soon be home to a new liquid X-ray machine that could improve catalysts.

The Liquid Phase Photoelectron Spectroscopy (LiPPS) machine will be the world’s first X-ray machine capable of studying the surface of liquids when it is installed at the university’s Nanotechnology and Nanoscience Centre (NNNC).

The LiPPS machine will analyse the surface of liquids by irradiating them with X-ray beams. ‘The X-ray is impinged onto the liquid surface and undergoes something called the photoelectric effect where it excites all the atoms at the surface,’ said Dr Peter Licence from Nottingham University’s department of chemistry. ‘It gives rise to a series of photoelectrons that are like a fingerprint for each of the atoms and elements that are within the catalytic surface.’

Licence explained that observing the surface of liquid catalysts would enable scientists to learn more about catalytic processes used in the production of chemicals.

‘This is the first time that data of this type has been able to be measured for liquid systems and solutions,’ he said. ‘Our machine is atomistic in nature so it can measure the electron density of the individual atoms at the catalytic surface.’

Being able to measure the electron density at the surface of a liquid is important because electron density is directly linked to the reactivity of a catalyst.

‘We can design better catalysts by changing the liquid environment,’ explained Licence. ‘We can either give it more electron density or take electron density away from it to make it more reactive and more selective.’

The team has been running experiments on a prototype machine but Licence said the researchers are in the process of commissioning and buying the EPSRC-funded £675,000 LiPPS machine, adding that it should be ready within the next six months.